Plants terrestrial or epilithic, evergreen, erect from decumbent or creeping main stems, 45-75 cm, with creeping subterranean rhizome and stolons. Rhizophores restricted to creeping rhizomes and stolons. Main stems pinnately branched from middle upward; branches not very regular, some much longer, unequally long, pale green or stramineous; unbranched main stem 15-30 cm tall, 1-2 mm in diam. in lower part, angulate, sulcate; primary leafy branches 5-8 pairs, 2 or 3 times pinnately branched, secondary branches once or twice pinnately branched, branchlets regular, adjacent primary branches on main stem 3.5-8 cm apart; leafy portion of main stem including leaves 6-9 mm wide at middle, ultimate branches 4-5 mm wide including leaves. Axillary leaves on main stems obviously larger than those on branches, broadly ovate, 2.5-4.5 × 2.4-3.6 mm, base not peltate, obtuse; axillary leaves on branches strongly asymmetrical, ovate, 3.5-4.2 × 1.9-2.8 mm, base exauriculate, margin slightly denticulate. Dorsal leaves ± symmetrical, those on main stems obviously larger than those on branches, dorsal leaves on primary branches contiguous or imbricate, oblong-lanceolate, 1.2-2 × 0.4-1 mm, slightly carinate, base truncate, margin denticulate, apex aristate. Ventral leaves asymmetrical, those on main stem obviously larger than those on branches; ventral leaves on primary branches spreading, ovate-triangular or oblong-falcate, 3-4.6 × 1.4-3 mm, apex subacute or obtuse; basiscopic margin entire; acroscopic base strongly enlarged, broader, overlapping stem and branches, margin subentire or minutely denticulate. Strobili solitary, compact, dorsiventrally complanate, 3-6.5 × 1.6-2.5 mm; sporophylls slightly dimorphic, resupinate, not white-margined; dorsal sporophylls ovate-lanceolate, margin denticulate, not keeled, apex acute, with sporophyll-pteryx incomplete and denticulate; ventral sporophylls ovate, carinate, margin denticulate; megasporophylls in basal portion on lower side of strobilus; microsporangia transversely elliptic; microspores pale yellow, megaspores whitish or pink.
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